<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .father{
            width: 300px;
            height: 300px;
            border: 1px solid red;
            /* 使用grid网格布局+ justify-self */
            display:grid;
        }
        .son{
            width: 100px;
            height: 100px;
            border: 1px solid rgb(90, 181, 197);
            justify-self: center;
        }
    </style>
</head>
<body>
    <div class="father">
        <div class="son">

        </div>
    </div>

</body>
</html>